MailBag

How Can MACD Rise when the Percent Price Oscillator Falls?

 | 



MACD and the Percentage Price Oscillator (PPO) both measure the difference between two moving averages, usually the 12-period EMA and the 26-period EMA. MACD measures the absolute difference, but the PPO measures the percentage difference by dividing this difference by the longer moving average. Even though these indicators usually track each other quite closely, differences will emerge when there are large price changes in the underlying security.

131129mailtsla1
Click this image for a live chart

The example above shows Tesla (TSLA) with a big price move as the stock advanced from the mid 30s to the low 190s in less than seven months. This 160 point gain (~450%) affected MACD and the PPO. After a decline in June, MACD continued to drift higher because the absolute difference in the moving averages remained high. The PPO, on the other hand, drifted lower because the “normalized” difference fell. As the calculation example for October 1st shows, the PPO divides the MACD value by the value of the 26-period EMA to show the difference in percentage terms, which makes it more comparable over time. While there is nothing wrong with MACD, I think the PPO provides a more robust picture of price momentum. You can read more about these indicators and many others in our ChartSchool.

Arthur Hill
About the author: , CMT, is a Senior Technical Analyst at StockCharts.com. He has written articles for numerous financial publications including Barrons and Stocks & Commodities magazine. Focusing predominantly on US equities and ETFs, his systematic approach of identifying trend, finding signals within the trend, and setting key price levels has made him an esteemed technician. In addition to his CMT designation, Arthur holds an MBA from the Cass Business School at City University in London. Learn More
Subscribe to MailBag to be notified whenever a new post is added to this blog!
thks for the fine compare/contrast concerning these two momentum indicators
comments powered by Disqus